The three changes of state during which energy is absorbed are:
1. Change from solid to liquid - Melting.
2. Change from liquid to gas - Vaporization
3. Change from solid to gas - Sublimation
All these changes of state require heat energy to break the attractive forces that hold the particles of the molecules together, so that they can move into more disorderly states. For instance, when heat is applied to a solid, the solid absorbs the heat and use it to break the attractive forces that are holding the molecules of the solid together. At a particular temperature, the attractive forces will be completely overcome and the solid framework will collapse, thus leading to the melting of the solid.
Answer:
The deceleration of the plane is 0.25 m/
.
Explanation:
Deceleration is the converse of acceleration.
From first law of motion, we have;
v = u + at
where: v is the final velocity, u is the initial velocity, a is the acceleration and t is the time taken.
Thus,
v = 50 m/s
u = 80 m/s
t = 120 s
50 = 80 + 120a
50 - 80 = 120a
-30 = 120a
a = 
= -0.25
a = -0.25 m/
The deceleration of the plane is 0.25 m/.
The hypothesis that all modern humans descended from an African lineage is supported by the mitochondrial DNA evidence. The Eve hypothesis is the hypothesis that is based on the study of mirtochodrial DNA; that modern humans have a common female ancestor who lived in Africa around 200,000 years ago. It is also called African Eve hypothesis.
Volcanic activity
fault lines
mnt. ranges
and siesmagraphs
